Official web site: sharpdx.org
SharpDX is an open-source project delivering the full DirectX API for .Net on all Windows platforms, allowing the development of high performance game, 2D and 3D graphics rendering as well as realtime sound application.
You can find more documentation on the Wiki
In order to compile SharpDX, you need to install the Windows 10 SDK 10.0.10586.0
A collection of Samples using SharpDX exists as a separate github project.